Motor vehicle windshield wiper having a parking position outside the wiping area

ABSTRACT

A windshield wiper for motor vehicles has a parking position of the wiper arm outside the wiping area, and includes a motor having a drive shaft, a crank guide member secured to the shaft, a resiliently biased crank member adjustable longitudinally of the guide member, switching means operable to initiate a parking movement and control means included in the switching means and engageable with a cam rotated with the crank member, upon activation of the switching means, to very the crank radius against the resilient bias. The control cam has, with respect to its direction of rotation, a steep ascent surface and an extended descent surface, which are engageable by the control member. Preferably the control cam is fixedly connected to the crank member and actuates an additional contact of the switching means only in the wiper parking position, to effect final switching off of the wiper motor.

all:

Schneider et al.

MOTOR VEHICLE WINDSHIELD [15] 3,694,723 [4 1 Sept. 26, 1972 3,057,9739/1962 Goodhouse ..200/l53.2 B WIPER HAVING A PARKING 3,117,335 1/1964Oishei et a]. ..3l8/DlG. 2 POSITION OUTSIDE THE WIPING AREA 7 PrimaryExaminerBernard A. Gilheany Assistant Examiner-F. E. Bell [72]inventors: Theodor Schneider Seestrasse 30,

7121 Freudental Wurttemberg; McGlew et Karl-Friedrich Schubert,Friedrich Naumannstrasse 10; Jacob Heinz, [57] ABSTRACT f l t S e o h of2 A windshield wiper for motor vehicles has a parking BletlgheimWurttemberg, all of Gerposition of the wiper arm outside the wipingarea, and y includes a motor having a drive shaft, a crank guide 22Filed: A 24 1971 member secured to the shaft, a resiliently biased crank1 member adjustable longitudinally of the guide PP 174,336 member,switching means operable to initiate a parking movement and controlmeans included in the [30] Foreign Application p i i Data switchingmeans and engageable with a cam rotated with the crank member, uponactivation of the 1970 Germany 20 64 4239 switching means, to very thecrank radius against the I resilient bias. The control cam has, withrespect to its 8 18/ 3%, direction of rotation, a steep ascent surfaceand an exo o u... t n d desc t u a are engageable the [58] F'eld Search18/443 200/1532 B control member. Preferably the control cam is fixedly[56] 7 Ref r C1 ed connected to the crank member and actuates an addiecum I tional contact of the switching means only in the wiper UNITEDSTATES PATENTS parking position, to effect final switching off of the W1er mo or. 2,546,077 3/l951 Peter ..200/l53.2 B p 2,996,585 8/1961 Lehde.t ..200/l53.2 B 5 Claims, 3 Drawing Figures MOTOR VEHICLE WINDSHIELDWIPER HAVING A PARKING POSITION OUTSIDE THE WIPING AREA FIELD OF THEINVENTION having a parking position of the wiper arm outside the wipingarea.

BACKGROUND OF THE INVENTION Application Ser. No. 121310, filed Mar. 23,1971, discloses a windshield wiper for vehicles, such as automotivevehicles, which has-a parking position, of the wiper arm, outside thewiping area. In this windshield wiper, upon switching off the wiperswitch, a switching means is energized and initiates a parking movementby varying the crank radius of the driven shaft of the motor. The crankconsists of a crank guide member fixedly connected to the driven shaftof the motor, and a crank member adjustable, within limits, in the crankdirection, this crank member being supported and guided by means of oneor more resilient elements. The crank also includes a control memberwhich, when parking is desired, projects into the path of movement ofthe crank member and varies the crank radius against the action of theresilient element or elements, to effect the additional parkingmovement. Either the control member of the switching means, or the crankmember, or both support control cams which cause a predetermineddisplacement of the crank member along the crank guide.

This windshield wiper has only a few and simple parts, which insuresmaintenance-free operation. However, when the driving motor is tumed onor energized, the crank is returned into the normal working position atsuch a speed that the wiper blades spring too quickly out of the parkingposition. Additionally, the final switching off or deenergization of thewiper motor causes difficulties. Yet a further disadvantage of such awindshield wiper consists in that the movement of the wiper blades intothe parking position does not occur if, when switching off, the crank isat a position immediately over the control member of the switchingmeans, so that the control cam cannot come into operation.

SUMMARY OF THE INVENTION The objective of the present invention is toimprove a windshield wiper of the type mentioned so that the mentioneddisadvantages are eliminated. Accordingly, the present inventionprovides a windshield wiper for vehicles, more especially for automotivevehicles, of the type disclosed in application Ser. No. 127,310, butwherein the control cam has a steep ascent surface and an extendeddescent surface considered with respect to its direction of rotation.

With the invention arrangement, the wiper parking position is reached atspeed when the wiper switch is moved to the off position. However, thewiper blades will not spring out of the parking position when the motoris energized to start the windshield wiper. Additionally, the wiperblades are moved safely into the parking position, independently of thecrank position, at the time when the wiper switch is moved to the offposition. The control cam is fixedly connected to the crank member andcontrols an additional contact which deenergizes the wiper motor whenthe blades are parked.

An object of the invention is to provide an improved windshield wiperfor motor vehicles of the type having a parking position of the wiperarm outside the wiping area.

Another object of the invention is ,to provide such a windshield wiperin which the wiper parking position is reached at speed when the wiperswitch is moved to the off position.

A further object is to provide such a windshield wiper in which thewiper blades will not spring out of the parking position when the motoris re-energized.

Another object of the invention is to provide such a windshield wiperincluding a control cam having, with respect to its direction ofrotation, a steep ascent surface and an extended descent surface.

For an understanding of the principles of the invention, reference ismade to the following description of a typical embodiment thereof asillustrated in the accompanying drawing. 7

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. 1 is a plan view of the crank driven by the shaft of the drivingmotor;

FIG. 2 is a sectional view through the crank; and

FIG. 3 is schematic wiring diagram of the windshield wiper installation.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, amotor driving shaft 10 has fixed thereto a crank guide member 11 whichis mounted for sliding movement between guides 16 and 17 and carries acrank member 15. Crank member 15 is biased in one direction along crankguide member 11 by a spring 13 covered by a sleeve 28.

The switching means comprises a solenoid 23 and a control member 24 inthe form of a ball bearing mounted roller which may be moved into thepath of movement of the crank by an armature 30, upon energization ofsolenoid 23. The crank carries a control cam 22 extending in the planeof rotation of the crank and, when solenoid 23 is energized, this cam,beginning at the point 32, moves crank 15 with respect to crank guidemember 11 in correspondence with the cam curve 33. Curve 33 extendsthrough only a limited angle of rotation of crank 15, and is fairlysteep, so that the parking movement is effected very quickly by changingthe crank radius.

Referring to FIG. 3, when wiper switch 50 is moved to the off position,solenoid 23 is energized since the retracted crank 11, l6, l7 retains anadditional contact 40 in the position shown in broken lines. The controlmembers 38 for this additional contact 40, as shown in FIG. 1, is leftunder control of the switching cam 37. When the additional contact 40 istransferred, switching solenoid 23 and motor M are disconnected from thesupply voltage. Motor M and solenoid 23 are short-circuited as shown bythe solid line position of contact 40, and this short-circuit of motor Mprovides a braking force which causes motor M to stop rapidly.

When wiper switch 50 is moved to an on position, motor M is energizedthrough either its terminal 53 or its terminal 53b. During rotarymovement of the crank, switching roller 24 is in rolling engagement withthe extended descent curve 34 of control cam 22. Descent curve 34extends through a greater angle of rotation than does ascent curve 33,so that wiper transfer from the parking position into the normal wipingposition is effected without any sudden movement of the wiper blade.When roller 34 reaches the terminal 39 of descent surface 33, the rollerdisengages the cam surface. This causes armature 30 of solenoid 23 toreverse its movement or to move inwardly, and the wiper movementcontinues with a reduced crank radius until switch 50 is again moved tothe off position.

Slider part 17, as best seen in .FIG. 2, carries switching cam 37 on itsunderside. Cam 37 deflects the operating lever 38, for actuating contact40, only when crank member 15 is displaced longitudinally of the crankradius, so that the crank radius is extended with switching means 23being energized.

Roller 36 of a contact 35 is also in rolling engagement along controlcam 22, andcontact 35 maintains solenoid 23 energized when switching offof the wiper is initiated. This obviates the necessity for a mechanicallock between switching means 23 and the crank.

While a specific embodiment of the invention has been shown anddescribed in detail to illustrate the application of the principles ofthe invention, it will be understood that the invention may be embodiedotherwise without departing from such principles.

What is claimed is:

l. A windshield wiper for motor vehicles, having a parking position ofthe wiper arm outside the wiping area, and of the type including a motorhaving a drive shaft, a crank guide member secured to the shaft, 21resiliently biased crank member adjustable longitudinally of the guidemember, switching means operable to initiate a parking movement andcontrol means in. cluded in the switching means and engageable withcontrol cam means rotatable with the crank member, upon activation ofthe switching means, to vary the crank radius against such resilientbias; in combination, said control cam means including a control camhaving, with respect to its direction of rotation, a steep ascentsurface and an extended descent surface, engageable by said controlmember.

2. A windshield wiper for motor vehicles, as in claim 1, wherein saidcontrol cam means is fixedly connected to said crank member.

3. A windshield wiper for motor vehicles, as in claim 1, including aswitch having contacts controlling connection of said motor to a sourceof potential; and an additional contact included in an energizingcircuit for said motor; said control cam means actuating said additionalcontact only when said switch is moved to the wiper parking position, toperform the final disconnection of said motor.

4. A windshield wiper for motor vehicles, as in claim 3, in which saidcontrol cam means includes a switching cam cooperable with saidadditional contact.

5. A windshield wiper for motor vehicles, as in claim 4, in which saidswitching means comprises a solenoid having an armature operating saidcontrol member;

said additional contact, when o erated b said switching cam,short-circuitmg said solenoid arid said motor.

1. A windshield wiper for motor vehicles, having a parking position of the wiper arm outside the wiping area, and of the type including a motor having a drive shaft, a crank guide member secured to the shaft, a resiliently biased crank member adjustable longitudinally of the guide member, switching means operable to initiate a parking movement and control means included in the switching means and engageable with control cam means rotatable with the crank member, upon activation of the switching means, to vary the crank radius against such resilient bias; in combination, said control cam means including a control cam having, with respect to its direction of rotation, a steep ascent surface and an extended descent surface, engageable by said control member.
 2. A windshield wiper for motor vehicles, as in claim 1, wherein said control cam means is fixedly connected to said crank member.
 3. A windshield wiper for motor vehicles, as in claim 1, including a switch having contacts controlling connection of said motor to a source of potential; and an additional contact included in an energizing circuit for said motor; said control cam means actuating said additional contact only when said switch is moved to the wiper parking position, to perform the final disconnection of said motor.
 4. A windshield wiper for motor vehicles, as in claim 3, in which said control cam means includes a switching cam cooperable with said additional contact.
 5. A windshield wiper for motor vehicles, as in claim 4, in which said switching means comprises a solenoid having an armature operating said control member; said additional contact, when operated by said switching cam, short-circuiting said solenoid and said motor. 